Experimental measurement of temperature-dependent sellmeier coefficients and thermo-optic coefficients of polymers in terahertz spectral range

Terahertz time-domain spectroscopy has been used to measure the temperature-dependent absorption coefficients and refractive indices of different polymers in 0.2–1.8 THz spectral frequency. The coefficients of temperature-dependent Sellmeier equation for all these polymers have also been evaluated by statistical fitting the measured data, which will be helpful for the evaluation of dispersion properties of the material. Additionally, the thermo-optic coefficients have been evaluated to be the range of −1.230×10−4 to −2.50×10−4 K−1 for 298–373 K. This data would be helpful for the applications of polymers as THz-waveguide and other temperature sensitive devices. These results provide a temperature-dependent database of optical properties of different polymers for their efficient utilization in THz technology.